Re: [PATCH v2 3/3] arm64: Silence first allocation with CONFIG_ARM64_MODULE_PLTS=y

From: Ard Biesheuvel
Date: Thu Apr 27 2017 - 14:12:49 EST




> On 27 Apr 2017, at 19:09, Florian Fainelli <f.fainelli@xxxxxxxxx> wrote:
>
>> On 04/27/2017 11:07 AM, Ard Biesheuvel wrote:
>>
>>> On 27 Apr 2017, at 18:39, Florian Fainelli <f.fainelli@xxxxxxxxx> wrote:
>>>
>>> When CONFIG_ARM64_MODULE_PLTS is enabled, the first allocation using the
>>> module space fails, because the module is too big, and then the module
>>> allocation is attempted from vmalloc space. Silence the first allocation
>>> failure in that case by setting __GFP_NOWARN.
>>>
>>> Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
>>> ---
>>> arch/arm64/kernel/module.c | 7 ++++++-
>>> 1 file changed, 6 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
>>> index 7f316982ce00..58bd5cfdd544 100644
>>> --- a/arch/arm64/kernel/module.c
>>> +++ b/arch/arm64/kernel/module.c
>>> @@ -32,11 +32,16 @@
>>>
>>> void *module_alloc(unsigned long size)
>>> {
>>> + gfp_t gfp_mask = GFP_KERNEL;
>>> void *p;
>>>
>>> +#if IS_ENABLED(CONFIG_ARM64_MODULE_PLTS)
>>> + /* Silence the initial allocation */
>>> + gfp_mask |= __GFP_NOWARN;
>>> +#endif
>>
>> Please use IS_ENABLED() instead here
>
> How do you mean?
>
> if (IS_ENABLED()) vs. #if IS_ENABLED()?
>

Apologies, I didn't read carefully.

Use the C if not the preprocessor if

>>
>>> p = __vmalloc_node_range(size, MODULE_ALIGN, module_alloc_base,
>>> module_alloc_base + MODULES_VSIZE,
>>> - GFP_KERNEL, PAGE_KERNEL_EXEC, 0,
>>> + gfp_mask, PAGE_KERNEL_EXEC, 0,
>>> NUMA_NO_NODE, __builtin_return_address(0));
>>>
>>> if (!p && IS_ENABLED(CONFIG_ARM64_MODULE_PLTS) &&
>>> --
>>> 2.9.3
>>>
>>
>> Other than that, and with Michal's nit addressed:
>>
>> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
>>
>
>
> --
> Florian